What is 7/9 of 57?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 7/9 of 57? We'll show you a straightforward method to achieve that.

How to calculate 7/9 of 57?

  1. Multiply the whole number by the numerator of the fraction: 57 × 7 = 399
  2. Divide this result by denominator of the fraction: 399/9 = 44.333333333333
  3. Simplify by dividing both the numerator and denominator by their GCD (3):
    • 399/3 = 133
    • 9/3 = 3
  4. Which gives: 133/3

Since 133/3 is an improper fraction, the result could also be expressed as a mixed number: 44 1/3

How does it work?

The principle behind finding a fraction of a number, such as 7/9 of 57, is rooted in the method of cross-multiplication.

Consider the following proportion: 7 9 = x 57 (where x represents 7/9 of 57)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 7 × 57 = 9 x
  2. Which gives: 399 = 9 x
  3. Divide both sides by 9 to isolate x: 399 9 = 9 x 9
  4. Which gives the result: 399 9 = x (or 133 3 = x )

Thus, 7/9 of 57 is equal to 133/3 (or 44.333333333333 in its decimal form).